Sri Lanka-Madagascar Gondwana linkage: Evidence for a Pan-African mineral belt

Sri Lanka occupies a unique geologic position in Gondwana. Recent age and i sotopic data suggest that the high-grade basement rocks of Sri Lanka are mo re closely associated with the southeastern part of Madagascar than with th e Archean granulites of southern and eastern parts of India. The occurrence s of gem minerals and graphite in the centrally located Highland Complex of Sri Lanka can also be correlated with those of the Kerala Khondalite Belt (KKB) at the southern tip of India and of southeast Madagascar south of the Ranotsara Shear Zone. These geological and mineralogical features indicate the juxtaposition of Sri Lanka with Madagascar and also with the Lutzow-Ho lm Bay area in Antarctica. The very close juxtaposition of Sri Lanka with M adagascar suggested here, which has hitherto been given only passing refere nce, implies that there exists a distinct mineralized belt running from Ant arctica through the Highland Complex of Sri Lanka into Madagascar, Mozambiq ue, Tanzania, and farther north. This mineral belt is clearly of Pan-Africa n origin and is now considered to be an important geosuture associated with the main Mozambique Belt. The position of Sri Lanka in Gondwana is of part icular significance because Sri Lanka acts as a bridge across the main East African and Antarctica crustal fragments.